Regular Article
Materials Science
Peverga Rex Jubu; Khaled M. Chahrour; Yushamdan Yusof; A. Nathan-Abutu; V. M. Igba; E. Danladi; O. S. Obaseki; M. B. Ochang; W. V. Zhiya; F. K. Yam
Abstract
The presence of multiple phases/ components within a nanocomposite material impacts its properties. Therefore, there is a need to estimate the phase fraction of each element present in a sample. Spurr-Myers proposed a valuable formula for calculating the rutile and anatase phase fraction of a TiO2 sample ...
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The presence of multiple phases/ components within a nanocomposite material impacts its properties. Therefore, there is a need to estimate the phase fraction of each element present in a sample. Spurr-Myers proposed a valuable formula for calculating the rutile and anatase phase fraction of a TiO2 sample from X-ray diffraction. However, this formula is dedicated to TiO2 and is inapplicable to samples that contain more than two phases. The present research proposed a simple method for quantifying the phase fraction of all types of nanomaterials consisting of two or more phases. The precision/ accuracy test, conducted by multiplying the total intensity of all the diffraction peaks present in a sample with the value of the phase fraction of individual components, showed that the proposed method gave precision values equivalent to the sum of the intensity of the peaks for each element. Meanwhile, the S-M gave precision values that were significantly inconsistent with the sum of the intensity of the peaks of each component. The study showed that the proposed method was valid for a wide range of 2θ values and can be deployed to obtain reasonable and reliable values of phase fraction that could assist in understanding the material phase fraction-properties relationship.
Regular Article
Nanotechnology
Rusul Mohammed Alsaffar; Balqees M. Al-Dabbagh; Hanaa K. Jawad
Abstract
This work compares two methods of producing carbon nanoparticles from oil waste or by-products that accumulate on the walls of pipes and furnaces and reduce the efficiency and life of the equipment (which can hinder the production process; therefore, it is removed weekly). These wastes or by-products ...
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This work compares two methods of producing carbon nanoparticles from oil waste or by-products that accumulate on the walls of pipes and furnaces and reduce the efficiency and life of the equipment (which can hinder the production process; therefore, it is removed weekly). These wastes or by-products are generated from the incomplete combustion of hydrocarbon compounds during the crude oil refining process to produce petroleum products. The raw materials were collected from two Al-Dura refinery sites, sieved, burned in a furnace under vacuum and inert atmosphere, crushed with a mortar and washed with solvent, washed with distilled water, dried, and then reduced to nanoparticle size by direct crushing (sonication with a probe) and indirect ultrasonic methods (bath sonication). The samples were analyzed after crushing and firing using the appropriate methods such as EDX and SEM as well as tests. Zeta potential and particle size analysis were two other tests performed on the final products. The results showed that the carbon content increased consecutively from 28.49, 36.30 to 91.59 and 94.47% after firing. In addition, the direct ultrasonic method is superior to the indirect method for producing carbon nanoparticles because it requires less time and can produce nanoparticles with an average grain size of about 37 nm and 86.6 nm for the first and second samples, respectively. The zeta potential data show that the resulting nanocarbon particles are relatively stable.
Regular Article
Laser Science and Technology
Mayyadah H. Mohsin; Khawla S. Khashan; Ghassan M. Sulaiman; Khalil A. A. Khalil
Abstract
A technique for exfoliating Boron nitride (BN) nanosheets was devised, which was then followed by a laser ablation-fragmentation process to produce lamellar hexagonal Boron nitride nanostructures (h-BNNs). The physicochemical properties of the nanoparticles were analysed to investigate the effect of ...
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A technique for exfoliating Boron nitride (BN) nanosheets was devised, which was then followed by a laser ablation-fragmentation process to produce lamellar hexagonal Boron nitride nanostructures (h-BNNs). The physicochemical properties of the nanoparticles were analysed to investigate the effect of laser energy and wavelength in the two-step pre-treatment procedure during BN synthesis. The X-ray diffraction (XRD) patterns showed no impurity phase structures, and only primary h-BN reflections were visible. It was discovered that the crystallite h-BNNs size ranged from 11 to 18 nm, and nanosecond laser energy was sufficient to transform BN into h-BNNs and a few nanotubes. Combining laser intensity and wavelength transformed the BN nanoparticle shape from haphazardly arranged platelets to melting-like formations. Fourier Transform infrared (FTIR) spectroscopy confirmed distinct observed changes in the size and melting behaviour in the h-BNNs and the sharp absorption peaks, which could indicate changes in their optical properties. Morphological characteristics and formation of the hexagonal phase of BN caused variations in optical properties and high-resolution transmission electron microscopy (HRTEM) results. Photoluminescence of h-BNNs was observed in the 250–600 nm range with peak emission at 485 nm. Due to its significant structural disorder, the h-BNNs exhibited a wide emission with a strong luminescence that remained largely continuous after 48 hours, resulting in a distinctive blue hue (470 and 485nm).
Regular Article
Applied Physics
Sura R. Mohammed; Mukhlis M. Ismail; Isam M. Ibrahim
Abstract
Polyaniline nanofibers (PAni-NFs) have been synthesised under various concentrations (0.12, 0.16, and 0.2 g/L) of aniline and different times (2h and 3 h) by hydrothermal method at 90°C. Was conducted with the use of X-ray diffraction (XRD), Fourier Transform Infrared spectra (FTIR), Ultraviolet-Visible ...
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Polyaniline nanofibers (PAni-NFs) have been synthesised under various concentrations (0.12, 0.16, and 0.2 g/L) of aniline and different times (2h and 3 h) by hydrothermal method at 90°C. Was conducted with the use of X-ray diffraction (XRD), Fourier Transform Infrared spectra (FTIR), Ultraviolet-Visible (UV-VIS) absorption spectra, Thermogravimetric Analysis (TGA), and Field Emission-Scanning Electron Microscopy (FE-SEM). The X-ray diffraction patterns revealed the amorphous nature of all the produced samples. FE-SEM demonstrated that polyaniline has a nanofiber-like structure. The observed typical peaks of PAni were (1580, 1300-1240, and 821 cm-1), analysed by the chemical bonding of the formed PAni through FTIR spectroscopy. Also, tests indicated the promotion of the thermal stability of polyaniline nanocomposite at temperatures above 600°C. Still, the PAni-0.12 g/L sample was better than the other samples, and the optical parameters manifested a decrease in the band gap (Eg) band gap. The observed TGA test findings also promoted polyaniline's thermal stability at temperatures reaching 600°C.
Regular Article
Materials Science
Ruaa Khalid Hamdan; Aqeel Al-Adili; Thamer Ahmed Mohammed
Abstract
This study presents an experimental measurements and three-dimensional simulation of time-varying scour, along with the variables affecting the resulted scour hole dimensions and evolution at center and side weirs. Slit weir location, crest level, flow rate and sediment size were tested within 34 steady ...
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This study presents an experimental measurements and three-dimensional simulation of time-varying scour, along with the variables affecting the resulted scour hole dimensions and evolution at center and side weirs. Slit weir location, crest level, flow rate and sediment size were tested within 34 steady and unsteady flow conditions under various flow rates 125, 95, 62, 50 and 34 L/s to study the scour behavior. All tests were carried out with non-uniform sediments of median sizes 0.24 mm and 0.55 mm. Steel slit weirs of 0.25 m width, 0.004 m thickness, and 0.07, 0.12 and 0.17 m crest level with respect to the mobile bed surface, which was constructed in a laboratory flume made up of brick and concrete within dimensions of (8 m, 1.25 m, and 1 m) long, wide and deep respectively. The present research demonstrates that maximum values of scour volume and scour depth obtained when the weir locate at center of the flume with flat crest for both steady and unsteady flow. Besides, the results indicated a low discrepancy between the experimental measures and the sediment scour model FLOW 3D software, both are showed a good agreement in presenting the scour development accurately as well as the model had excellent ability in predicting the velocity magnitudes at the slit location and the values of shear stress which was hard to measure directly.
Regular Article
Chemistry
Sara Salam Ali; M. S. Ali; Abdulnasser M. Al-Gebori; Hassanien Ahmed Hadi Al-Jumaily; Poh Choon Ooi; Asalnov Jamaladdin Nuraddin
Abstract
Periodontal disease is a common disease and may affect 90% of people and is classified into gingivitis and periodontitis. The objective of this study was if the deficiency of some vitamins and trace elements affects the increase in exposure to periodontal diseases or to find out whether the periodontal ...
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Periodontal disease is a common disease and may affect 90% of people and is classified into gingivitis and periodontitis. The objective of this study was if the deficiency of some vitamins and trace elements affects the increase in exposure to periodontal diseases or to find out whether the periodontal disease can cause changes in the blood level of some nutrients and their role in reducing periodontal diseases. For this purpose, samples were collected from the University of Baghdad, College of Dentistry, Department of Periodontics, Periodontics Clinic, including a group of 40 patients with periodontitis and another 40 patients with gingivitis and 40 healthy periodontal patients as controls. There was no overall sickness in any of the groups. Periodontal clinical data were recorded, and serum parameter levels were assessed. The findings showed that plaque index, bleeding on probing, probing pocket depth, and clinical attachment loss were significantly greater (P< 0.01) in patients compared to the control. Levels of vitamin C and D were significantly decreased in patients compared with control (P<0.01), while levels of copper were high significant increase) in the patients compared to the control, and zinc show a highly significant increase in the periodontitis group. A negative correlation was found between vitamin D with BOP and PLI, in conclusion, low levels of C and D are associated with a risk factor for periodontal disease and contribute to the development of the disease, and high levels of copper and zinc play an important function as an indication of periodontal disease.
